Communication privacy over two-way way radios is very desirable to many users, such as public safety users in law enforcement, emergency rescue, and fire departments, as well as to business users covering important commercial events, such as political rallies, concerts, and sporting events and the like. There are various techniques for key encryption including dedicated hardware modules and software-based encryption in the radio's existing processor. Additionally, there are various key generation, storage and distribution techniques ranging from complex and expensive to simple and inexpensive.
Many radio users desire some reasonable privacy but do not need or require highly secure (government-grade) cryptography. These users do not want, do not need, and/or are not willing to pay for an expensive Key Variable Loader. Such users may prefer a “software only” approach that uses Customer Programming Software (CPS) to program and manage keys via encryption software running on a processor already present in the radio. However, this software approach still requires a communication cable and a PC or laptop to program keys. This can be inconvenient for keyloading or rekeying a radio, and it can be particularly cumbersome in the field. Users are less likely to change keys, because each radio must encounter a CPS programming station to update the key. The lack of key change may potentially create security issues over time. Those skilled in the art will appreciate the need to coordinate key changes to avoid a disruption in communication. While over-the-air rekeying is a possible approach, however, for some classes of users this technique is too complex and/or too costly as it involves centralized equipment and systems.
The ability to provide increased privacy to various users and applications including public safety, business and even private individuals is thus highly desirable. Accordingly, there is a need for a method and apparatus for improved key distribution.
Skilled artisans will appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of embodiments of the present invention.
The apparatus and method components have been represented where appropriate by conventional symbols in the drawings, showing only those specific details that are pertinent to understanding the embodiments of the present invention so as not to obscure the disclosure with details that will be readily apparent to those of ordinary skill in the art having the benefit of the description herein.